4-Phenylpiperidines, which have an antidepressive, anti-aggressive, diuretic, anti-Parkinson, bronchodilatory and anti-arthritic activity, are described in German Offenlegungsschrift DE-OS No. 2,735,051. Significant to the pharmacological activity of these compounds is the presence of a hydroxyl group, or an ester derivative thereof, in the 3-position of the piperidine ring; esterified hydroxyl groups in the 3-position and 4-position of the piperidine ring are stated to be of particular importance. In contrast, certain 4-phenoxypiperidines which are unsubstituted in the 3-position now display pharmacologically-interesting and specific properties.